Lift Assist stops moving downward

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DAVC3
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Lift Assist stops moving downward

Post by DAVC3 »

The lift assist on my Mark 500-520 Upgrade does not allow me to move the headstock carriage down smoothly. On the downward motion, it stops at an angle of about 25 degrees (roughly). Previously, there was a popping noise when the headstock went through that point. Now, the carriage stops. I don't want to force it in case there's a danger of damaging the machine. There is no resistance on the moving the headstock carriage upright.

The popping noise and the latest stopping at the 25 degree angle is new.
What's wrong?
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chapmanruss
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Re: Lift Assist stops moving downward

Post by chapmanruss »

Lets make sure we are talking about the same item. Is it the Lift Assist you are talking about as shown in the picture below?
Lift-Assist.jpg
Lift-Assist.jpg (18.37 KiB) Viewed 1718 times
Next do you have the Power Pro Headstock or the conventional Headstock? If this is what we are talking about for the Lift Assist and you have the conventional Headstock do you know which model of Lift Assist you have? There are four models which depends on when it was made and which Headstock you have. The cylinder has a conventional and Power Pro version since the Power Pro Headstock weighs more than the conventional one. The other difference is for its mounting to the frame depending on when it was made. Could you have a Power Pro version and are using it on a conventional Headstock Mark V?
Russ

Mark V completely upgraded to Mark 7
Mark V 520
All SPT's & 2 Power Stations
Model 10ER S/N R64000 first one I restored on bench w/ metal ends & retractable casters.
Has Speed Changer, 4E Jointer, Jig Saw with lamp, a complete set of original accessories & much more.
Model 10E S/N 1077 oldest one I have restored. 10E S/N 1033 & Mark 2 to be restored.
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reible
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Re: Lift Assist stops moving downward

Post by reible »

Stopping and popping are not normal.

Do you have the installation instructions? If so you might want to review them. Things need to be located and if they are not then who knows what might that might cause.

In the mean time I think it wise to disconnect the cylinder and not depend on that for the lift. I have not heard of one of these failing but I have had one fail on my Ford Escort hatchback. Gave me a good knock on the head and having the shopsmith fall could/would be much worse for both of you.

If you don't have the instructions I or someone else can make a copy for you, just ask.

Ed
{Knight of the Shopsmith} [Hero's don't wear capes, they wear dog tags]
DAVC3
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Re: Lift Assist stops moving downward

Post by DAVC3 »

chapmanruss wrote:Lets make sure we are talking about the same item. Is it the Lift Assist you are talking about as shown in the picture below?

Lift-Assist.jpgNext do you have the Power Pro Headstock or the conventional Headstock? If this is what we are talking about for the Lift Assist and you have the conventional Headstock do you know which model of Lift Assist you have? There are four models which depends on when it was made and which Headstock you have. The cylinder has a conventional and Power Pro version since the Power Pro Headstock weighs more than the conventional one. The other difference is for its mounting to the frame depending on when it was made. Could you have a Power Pro version and are using it on a conventional Headstock Mark V?
Your photo matches the Lift Assist on my machine. I upgraded to the Power Pro and got the Lift Assist because the headstock weighs more than the conventional one. The model number is 555975.
DAVC3
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Re: Lift Assist stops moving downward

Post by DAVC3 »

reible wrote:Stopping and popping are not normal.

Do you have the installation instructions? If so you might want to review them. Things need to be located and if they are not then who knows what might that might cause.

In the mean time I think it wise to disconnect the cylinder and not depend on that for the lift. I have not heard of one of these failing but I have had one fail on my Ford Escort hatchback. Gave me a good knock on the head and having the shopsmith fall could/would be much worse for both of you.

If you don't have the instructions I or someone else can make a copy for you, just ask.

Ed
I have the instructions and followed them precisely. At first - a couple of years ago - the Lift Assist worked beautifully. Now, this problem. I'll disconnect the cylinder until I can figure out the problem. Lifting the headstock up and down will take the place of going to the gym. :)
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wa2crk
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Re: Lift Assist stops moving downward

Post by wa2crk »

stopping and popping should not be heard. They could indicate that something is binding and then releasing. Try removing the gas pressure tube and check to see if the popping stops. If it does very closely check the castings of the lift assist for cracks especially in the welds. The gas strut puts a lot of stress on the components. Also check to see if the clamps that hold the way and bench tubes to the end castings are tight and there is no movement in the associated parts. After this if you still have the popping noise check with Shopsmith to see if the gas strut is under any kind of warranty.
Bill V
DAVC3
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Re: Lift Assist stops moving downward

Post by DAVC3 »

ShopSmith finally replied that I need a new gas cylinder. The price is $61.40, which seems expensive compared to gas cylinders for car tailgate lifts. Are there similar gas cylinders that can be used, which are less expensive?

Thanks.
David
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ryanbp01
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Re: Lift Assist stops moving downward

Post by ryanbp01 »

Do car tailgate lifts use, or have, the same diameter knobs which the cylinder on the lift assist attaches? Also, a lot of the liftgates use two cylinders. I suppose you could take the cylinder to an auto supply store, but I think you will be out of luck.
BPR
DAVC3
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Re: Lift Assist stops moving downward

Post by DAVC3 »

wa2crk wrote:stopping and popping should not be heard. They could indicate that something is binding and then releasing. Try removing the gas pressure tube and check to see if the popping stops. If it does very closely check the castings of the lift assist for cracks especially in the welds. The gas strut puts a lot of stress on the components. Also check to see if the clamps that hold the way and bench tubes to the end castings are tight and there is no movement in the associated parts. After this if you still have the popping noise check with Shopsmith to see if the gas strut is under any kind of warranty.
Bill V
The popping noise (one pop on the way down) has stopped when I move the carriage down. But the resistance going going down is still there and at about 23-25 degrees, the headstock carriage will still stop. Extra force downward will push it through the resistance The end castings on the bench tubes are tight - a couple of bolts were snug and those were tightened more. I bought the Lift Assist three years ago, so it is out of warranty now.

I'll try an auto parts store to see if it has something similar.

Thanks everyone for your tips.

David
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chapmanruss
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Re: Lift Assist stops moving downward

Post by chapmanruss »

Keep in mind when looking for a non OEM replacement that there are different strengths/pressures for these types of cylinders. Getting one to strong may keep your Shopsmith from going back down from drill press position or worse yet "launch it" when going to drill press mode. Getting one to weak could be little better than not having it at all but much better than one that is to strong. It is the same reason Shopsmith sell two different cylinders. One for the standard headstock and one for the Power Pro headstock.
Russ

Mark V completely upgraded to Mark 7
Mark V 520
All SPT's & 2 Power Stations
Model 10ER S/N R64000 first one I restored on bench w/ metal ends & retractable casters.
Has Speed Changer, 4E Jointer, Jig Saw with lamp, a complete set of original accessories & much more.
Model 10E S/N 1077 oldest one I have restored. 10E S/N 1033 & Mark 2 to be restored.
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